We introduce indium zinc oxide (IZO) thin films grown at room temperature by using a low-frequency (LF) 60Hz magnetron sputtering system. The flexible substrates are PES, PET and PC. The optical, electrical and structural properties of IZO films on flexible substrates were investigated. The alloy target was In2O3:ZnO (90:10wt%) with a diameter of 3 inch and thickness of 5 mm. The vacuum chamber was evacuated down to pressure 5 x 10(-6) torr prior to deposition. The flow rates of argon gas (99.999%) were kept at a constant value of 30 scem by a mass flow controller(MFC). The discharges were performed by power of 300 V, 310 V, 320 V. They have low sheet resistance of about 30 Omega/sq., high transmittance of over 85% in the range of 400-700nm. Also they showed good band gap of about 3.43eV on polyethersulfone (PES) substrates, 3.50 eV on polyethylene terephthalate (PET) and 3.30 eV on polycarbonate (PC). The experimental results imply that the films with good qualities in surface morphology, transmittance and electrical conduction can be grown by a low-frequency magnetron sputtering method an PES is the most recommendable substrate.